This invention relates to non-destructive material evaluation, and in particular, to a method for characterizing, visualizing, and evaluating integrity and thermophysical properties of conducting material samples or complex structures.
A variety of nondestructive evaluation technique are used for evaluating the integrity of simple and composite materials. They include radiographic (x-ray and neutron), optical, acoustic, ultrasonic, electromagnetic, and thermographic techniques. These various methods are best suited for detecting different types of flaws.
Thermographic methods are based on the principle of thermal imaging of heat patterns. The most common methods of thermal imaging are a chemical method employing liquid crystals and an electronic method employing an infrared camera.
The present invention is useful in the thermal imaging of conducting materials, and is particularly useful in the measurement of thermal conductivity and thermal boundary conditions in composite non-isotropic materials, in material samples of irregular shape, and in materials for high temperature applications.
The present invention has utility as well in characterizing and visualizing the integrity of complex structures (i.e. a machine, a power plant, a chemical plant, etc.) and provides a tool for determining the exact magnitude and location of even small anomalies.
Therefore a primary object of this invention is to provide a method for evaluating thermophysical properties of a conducting material sample or structure (herein called a system).
In the accomplishment of the foregoing object, it is another important object of this invention to provide a method for mapping electrical resistance throughout a conducting continuous system.
It is another important object of this invention to provide a graphical representation of a system in terms of its electrical resistance which is useful in visualizing temperature distribution or monitoring the integrity of the system.
It is a further object of this invention to present a method for identifying the dependence of electrical resistance on temperature for a specific system, in both time and steady state.
A yet further object of the present invention is to present a method for system characterization of thermophysical properties which is non-intrusive and non-destructive to the conducting system.
Additional objects, advantages and novel features of the invention will become apparent to those skilled in the art upon examination of the following and by practice of the invention.